def multiple_square(N1, N2):
    list_result = []
    for x in range(N1, N2+1):
        if x%3 == 0:
            list_result.append(x**2)
    return list_result


assert multiple_square(4, 13) == [36, 81, 144]
assert multiple_square(18, 22) == [324, 441]
assert multiple_square(54, 54) == [2916]